JP2006506537A - Apparatus and method for forming materials - Google Patents

Abstract

The present application relates to an extrusion device comprising at least one first reservoir (1) connected at a first opening and a first end of a plurality of adjustment modules (4). The adjustment module or spinneret includes a cylindrical passage (17) through which the dope material (25) can be extruded. The extrusion device (4) has at least 1,000 cylindrical passages (17) per square meter of cross-sectional area.

Description

  The present invention relates to an apparatus and method for forming extruded materials, such as filaments, fibers, ribbons, sheets or other solid products, from liquid solutions such as polymer solutions (the term includes protein or cellulose solutions).

  Methods for producing filaments or fibers have long been known in the art. For example, melt spinning techniques are used to produce fibers from polymer solutions. British Patent Application No. 441440 (Ziegrer) discloses a technique for producing filaments by passing a liquid raw material for solidification through a porous porcelain tube. In this disclosure, the filament emerges from the end of the porous porcelain tube. The working medium is introduced into the porous porcelain tube through the pores of the tube.

  Recently there has been considerable interest in the development of improved processes and equipment that allow the production of polymer filaments, fibers, ribbons or sheets. It is theoretically possible to obtain materials with high tensile strength and toughness by manipulating the orientation of the macromolecular molecules and the way they interact with each other. Strong, tough filaments, fibers or ribbons are naturally useful in the manufacture of, for example, sutures, yarns, cords, ropes, wound or woven materials. They can also be incorporated into the substrate with or without other filler particles to produce a tough elastic composite. Sheets formed from either fibers or ribbons can also be stacked together to form a tough laminated composite.

  Natural silk is a fine, shiny filament produced from Bombyx mori and other invertebrate species. They have advantages compared to the synthetic polymers currently used for the production of materials. The tensile strength and toughness of certain silkworm dragline silks can exceed the strength and toughness of Kevler ™, the toughest and strongest artificial fiber. Silkworm bookmark silk also has high thermal stability. Many silks are biodegradable and do not remain in the environment. They are recyclable and are produced in a highly efficient low pressure and low temperature process using only water as a solvent. The natural spinning process is surprising in that it results in an aqueous protein solution resulting in a tough, highly insoluble material.

  Natural silk Has been reported to be produced by elaborate spinning techniques that cannot yet be reproduced with artificial spinning techniques.

  Fibers produced by existing technical processes and equipment have the following disadvantages. Many exhibit “die swell” which results in some loss of molecular orientation, resulting in degradation of mechanical properties. Furthermore, existing processes are not energy efficient and require high temperatures and pressures to reduce the viscosity of the feedstock and allow the feedstock to be extruded through a die. Another step is often necessary, for example, for further “draw-down”, such as annealing the fiber with heat and passing the fiber through another acid or alkali treatment bath.

  An example of an improved method of producing fibers is known from EP 0 656 433 (Filtration Systems, Inc. and Japan Steel Works, Ltd.), which includes a nozzle with a plurality of spinning holes. Teach the plate. However, this document does not address the die swell problem that occurs when spun fibers or filaments exit the nozzle plate exit.

  A system for producing multicomponent composite fibers is known from EP-A-0104081 (Toray Industries). This application discloses a spinneret assembly that produces "island-in-sea" type fibers using multiple feedstocks. The spinneret assembly can include a plurality of nozzles for producing a plurality of fibers simultaneously. However, this document does not teach fiber dimensions and device dimensions.

  There is still a need to rapidly produce a large number of high strength fibers.

  These and other objects of the present invention include at least one first reservoir connected at a first end and a first end of a plurality of adjustment modules including a passage through which material can be extruded. It is solved by providing an extrusion device having. The extrusion device has at least 1,000 passages per square meter of cross-sectional area. By using this apparatus, a large number of fibers can be rapidly produced. The passage can be, for example, cylindrical or ribbon-shaped.

  In an advantageous embodiment of the extrusion device, the adjustment module further comprises at least one second reservoir. Multicomponent fibers can be produced by using the second storage tank.

  The extrusion device further comprises a sensor such as a pressure sensor, a temperature sensor, a chemical sensor, a pH sensor, and / or a light scattering sensor. These sensors measure the parameters of the extrusion process and can quickly adjust the extrusion conditions if necessary.

  These sensors are preferably integral with the adjustment module. In this embodiment, the sensor is not configured as a separate component, but is formed as part of the adjustment module.

  The extrusion device can also have a pump in the conditioning module for pumping the feedstock through the extrusion device. Such a pump can be a piezoelectric pump, a vibration pump or other known pumps.

  The passage may have a flow inlet. These flow inlets allow another material to be added to the feed during the extrusion process. Such another material may include a dopant that alters the properties of the finally extruded material. This alternative material can also advantageously modify this extrusion process.

  In one aspect of the invention, the inner wall of the cylindrical passage is made of a permeable material. This allows another material to be incorporated into the final extruded material to diffuse through the inner wall. This adjustment module can be manufactured, for example, by either injection molding or laser ablation.

  In order to avoid die swell problems that can lead to a reduction in mechanical strength during use, the material is drawn down at least 0.5 mm from the outer outlet opening in the cylindrical passage for the initial distance.

  Internal drawdown is aided by providing a ridged surface on the inner surface of the tubular passage. The height of the ridge on the ridge surface is usually less than 10% of the diameter of the tubular passage. The ridges on the ridge surface are substantially continuous and are oriented substantially parallel to the longitudinal axis of the tubular passage. This ridge is preferably made of a hydrophobic material or coated with the same material.

  The discovery of how to make silkworm silk silk has provided the basis for the present invention. We make the tubular passage or the wall of each tubular passage at least partially permeable or porous, preferably selectively permeable along the length of the tubular passage, preferably the tubular passage It has been found that by tapering the passages, the properties of the spinning solution such as pH, moisture content, ionic composition and shear regime can be controlled in different regions of the extrusion die cylindrical passage. . This ideally makes it possible to control the phase equilibrium diagram of the spinning solution, allowing pre-orientation of the fiber-forming molecules that follow shear-induced phase separation, and well-oriented fiber-forming molecules. Allows the formation of insoluble fibers containing.

  Conveniently, the wall defining such a cylindrical passage is surrounded by said surrounding means so as to form one or more compartments. These compartments function as a jacket around one or more cylindrical passages. Such a cylindrical passage is preferably divided into three parts which are arranged in succession, preferably with an inlet for receiving the spinning solution at one end and an outlet for the material formed or extruded at the other end. The The first portion or first zone allows pre-treatment and pre-orientation of the molecules of the fiber-forming polymer in the liquid feed material prior to forming the material by drawdown, and the second region or next zone is A “yarn” drawdown occurs therein and functions as a treatment and coating bath, with the third part or last zone having a limited cross-section outlet or opening and accompanying the outgoing fiber It serves to prevent loss of the “treatment bath” content and to initiate an optional air suction stage.

  If the solution or solvent or one or more other phase (s) surrounds the fiber in the cylindrical passage or the second portion of each cylindrical passage, the fiber moves through the cylindrical passage and exits It can also be seen that it also serves to lubricate the fibers.

  In another aspect of the invention, the tubular passage or the wall of each tubular passage can include an inlet through which another material can be introduced into the tubular passage. This other material can change the state in which the extrusion process is taking place, or can be incorporated as a dopant in the final extrusion material.

  In one embodiment of the invention, a coating can be applied on the fibers or extruded material by openings that communicate into or surround the first zone or the second zone of the tubular passage.

  All or a portion of the length of each cylindrical passage typically has a tapered shape that typically decreases in diameter in a substantially hyperbolic fashion. According to GY Chen, JA Cuculo and PA Tucker in the literature entitled “Characteristics and Design Procedure of Hyperbolic Die” in the 1992 Journal of Polymer Sciences: Part B: Polymer Physics, Vol 30, 557-561 It has been reported that the molecular orientation of can be improved by using a die having a tapered hyperbolic shape instead of the more conventional parallel capillary or conical die.

  The shape of virtually all or part of the cylindrical passages or each cylindrical passage is changed to optimize the longitudinal flow rate in the spinning solution (dope) and to change the cross-sectional shape of the forming material produced therefrom. can do. The preferred substantially hyperbolic taper for the tubular passage or a portion or all of each tubular passage maintains a slow, substantially constant longitudinal flow rate, so that longitudinal flow rate variation or dope is adequate Prevent undesired non-orientation of the fiber-forming molecules as a result of premature formation of insoluble material before reorientation. Longitudinal flow is induced by a tapered taper to the cylindrical passage of the die, and by utilizing the well-known principle of longitudinal flow, it is substantially axial to the fiber-forming molecules, short fibers or packed particles contained within the dope. A tendency to induce orientation alignment is provided. Alternatively, use the principle of longitudinal flow by the divergent portion of the die instead of a tapered die to induce a hoop orientation that is substantially transverse to the direction of flow through the divergent portion of the die. can do.

  The diameter of the tubular passage or each tubular passage can be varied to produce fibers of the desired diameter. In the embodiments of the invention disclosed herein, the diameter of the tubular passage or each tubular passage must be selected to produce at least 1000 fibers per square meter.

  The rheology of the liquid feed material in the cylindrical passage of the die is almost scale independent. Thus, the dimensions of the device can be scaled up and down. By tapering the cylindrical passage, a wide range of withdrawal speeds, usually in the range of 0.01 to 1000 mm / sec, can be used. If the fibers are extruded, they usually have a diameter of 0.1 to 100 μm. Typically, the outlet of the cylindrical passage has a diameter of 1 to 100 μm, and the diameter of the inlet of the cylindrical passage is 25 to 150 times larger depending on the extension flow that it is desired to produce. Other cross-sectional cylindrical passages can also be used to produce extruded fibers, flat ribbons or sheets having different cross-sectional shapes.

  All or part or portions of the tubular passage or each tubular passage wall of the die assembly is composed of a selectively permeable and / or porous material such as a cellulose acetate based membrane sheet, Formed or cast. This membrane can be substituted with diethylaminoethyl or carboxyl or carboxymethyl groups to help keep the protein-containing dope in a state suitable for spinning. The membrane can also be made substantially hydrophobic with siliconized or silanized solutions, or polytetrafluoroethylene particles. Another example of a permeable and / or porous material is a hollow fiber membrane, such as a hollow fiber composed of polysulfone, a polyethylene oxide-polysulfone mixture, silicone or polyacrylonitrile. The exclusion limit chosen for the semipermeable membrane depends on the small molecular weight size of the dope components, but is usually less than 12 kilodaltons (kDa).

  All or part of the tubular passages or the walls of each tubular passage can be constructed in a number of different ways from selectively permeable and / or porous materials. By way of example only, a selectively permeable and / or porous sheet may be cut into a piece of material having an appropriate shape and held in place over the groove to form a cylindrical passage. Can be. As an alternative, two sheets of selectively permeable and / or porous material can be held in place on either side of the separator to form a cylindrical passage. As an alternative, a single sheet can be bent round so as to form a cylindrical passage. A hollow tube of selectively permeable and / or porous material can also be used to construct all or part of this cylindrical passage. By way of example only, various methods can be used to form a tube in a die, as is commonly known to those skilled in the art.

  Furthermore, the inner wall can be provided with “bumps” or bumps that are virtually smooth or at least part of the wall. Such a modification in the wall helps the drawdown process. Such ridges or bumps are usually less than 10% of the diameter of the cylindrical passage.

  By using selectively permeable and / or porous walls in virtually all or part or portions of this tubular passage, for example, the concentration of the dope fiber-forming material in the tubular passage, Appropriate solute, ionic, pH, insulation properties, osmotic potential and other physicochemical properties within desired limits by applying well-known principles of dialysis, reverse dialysis, ultrafiltration and pre-evaporation Will be able to control. Electro-osmosis can also be used to control the composition of the dope in the cylindrical passage. For example, a control mechanism that receives input about the product to be formed, such as the diameter of the extruded product during extrusion through the outlet of the cylindrical passage and / or the reverse resistance in the cylindrical passage, It should be understood that it can be used, for example, to control polymer concentration, solute components, ionic components, pH, insulating properties, osmotic potential and / or other physicochemical properties.

  This tubular passage or each tubular passage wall is selectively permeable and / or porous, so that another substance can be made of the selectively permeable material that forms the wall of the tubular passage. If it has a molecular weight below the exclusion limit, it can also diffuse through the wall into the cylindrical passage. By way of example only, additional materials thus added to the dope include surfactants, dopants, coating agents, crosslinking agents, curing agents, plasticizers, and the like. If the wall of the tubular passage is simply not semi-permeable and porous, larger size aggregates can pass through the wall.

  The compartment surrounding the wall of the tubular passage or passages can function as one or more zones or baths for conditioning the fibers as they pass through the tubular passage. Additional processing can also be performed after the material exits the cylindrical passage.

  A jacket or a plurality of jackets or a plurality for holding a solution, solvent, gas or vapor in contact with the outer surface of the selectively permeable wall of the cylindrical passage or one or more regions of each cylindrical passage; It can be surrounded by one or more compartments arranged in series to function as a jacket. The solution, solvent, gas or vapor is usually circulated through the compartment or compartments. The wall of the compartment or compartments is sealed against the outside of the wall or walls of the tubular passageway in a manner that will be understood by those skilled in the art. The compartment or compartments serve to control the chemical and physical conditions within the tubular passage or each tubular passage. Accordingly, the compartment surrounding the cylindrical passage serves to define the correct processing conditions within the dope at any point along the cylindrical passage. In this way, as the dope moves down the die length, temperature, static pressure, concentration of fiber forming material, pH, solute component, ionic component, dielectric constant, osmotic pressure or other physical or chemical Parameters such as parameters can be controlled in different areas of the cylindrical passage. By way of example only, a continuous transition or a step change in the processing environment can be obtained.

  Conveniently, a selectively permeable / porous membrane can be used to treat on one side of the extruded material formed, in a different manner than the other side. This can be used, for example, to coat the extrusion material asymmetrically or to remove the solvent therefrom so that the extrusion material can be curled or twisted.

  Sensors can be included in the cylindrical passage to measure parameters such as temperature, pressure, chemical composition, pH and / or light scattering. Sensor results can be used to dynamically change the processing parameters of the extrusion process. The light scattering sensor can detect the presence, size and distribution of particles within the dope and can determine whether the dope is in a sol or gel state by appropriate software.

  All or part of the drawdown process typically occurs within the die's cylindrical passage, rather than at the outer surface of the die assembly as occurs with existing spinning equipment. This process offers advantages over existing spinning equipment. Twisting of molecular alignment due to die expansion is avoided. The area of the die assembly after the start inside the drawdown taper can be used to apply a coating or treatment to the extrusion. Furthermore, the last part of the die assembly is water lubricated by the solvent rich phase surrounding the extrusion.

  By way of example only, the device comprises a silkworm recombinant silk protein or analogue, or a silkworm recombinant silk protein or analogue, or a mixture of such proteins or protein analogues, or a regenerated silk solution from silkworm silk. Can be used to form fibers from solution dopes. When using these dopes, it is necessary to store the dopes at a pH above a threshold that prevents premature formation of insoluble materials. It should be understood that other components can be added to the dope to keep the protein or protein analog in solution. These constituents are then semi-permeable and / or porous when the dope reaches the appropriate part of the cylindrical passage where it is desirable to induce the transition from a liquid dope to a solid product, such as yarn or fiber. Can be removed through quality walls. The dope in the cylindrical passage is then contacted by dialysis with an appropriate acid or base or buffer solution to induce or cause aggregation or structural change in one or more of the constituent proteins of the dope, or close to it. It can be brought to the pH value. Such a pH change promotes the formation of insoluble materials. Volatile bases or acids or buffering agents can also be used to adjust the dope pH to the desired value from the vapor phase in the compartment or jacket surrounding the tubular passage, and the walls of this tubular passage or each tubular passage. Can diffuse through. Vapor phase treatment to adjust the pH can also take place after the extruded material has left the die assembly outlet.

  The draw speed and the length, wall thickness, shape and material composition of this or each cylindrical passage can be varied along its length to yield different residence times and processing conditions that are optimal for the process. .

  One or more regions of this cylindrical passage or the walls defining each cylindrical passage may be articulated in the art by means of suitable materials to modify the internal environment of the length of the cylindrical passage. It can be rendered impermeable by coating using any coating method understood by the person skilled in the art.

  The inner surface of this tubular passage or the wall of each tubular passage can be coated with a suitable material to reduce the friction between the wall of the tubular passage and the dope or fiber. Such a coating can also be used to induce proper interfacial molecular alignment of the liquid crystal molecules at the wall of the cylindrical passage when the liquid crystal polymer is included in the dope.

  According to another embodiment, two or more different dopes are coextruded through the same cylindrical passage so that the fiber or fibers can be formed with one or more coatings or layers. Thus, one or more additional components can be supplied to this tubular passage or the starting point of each tubular passage through concentric openings.

  Another embodiment uses a dope prepared from a phase-separating mixture containing, for example, two or more components that are different proteins. By removing or adding constituents through selectively permeable and / or porous materials, one or more of the constituents, usually 100 to 1000 nm in diameter, in the fiber phase at the final extrusion. The phase separation process can be controlled to produce drops. They can be used to increase the toughness and other mechanical properties of the extruded material. By using a tapered or divergent die, an elongate flow is conveniently induced in the droplets, resulting in oriented elongated packed particles or cavities in the fiber phase. Tapered dies direct such droplets in a direction parallel to the direction of the product to be formed, while elongate dies cross the direction of flow of each particle in the dope cylindrical passage. So that the droplets in the hoop tend to face. Both types of arrangements can be used to enhance the properties of the product formed. In addition, this tubular passage or the selectively permeable and / or porous walls of each tubular passage are used to enter and exit chemicals that initiate the polymerization of the packed particles. Please understand that you can.

  An extrusion apparatus having one or more cylindrical passages surrounded by a compartment or compartments functioning as a jacket is a one or two stage casting or other method known to those skilled in the art. Can be assembled by. This jacket need not completely surround the cylindrical passage. The jacket can have different shapes as required. It should be understood that a casting process can be used to create a simple or complex shape of this tubular passage or each tubular passage and the outlet of the die assembly. A very small, flexible lip prevents the treatment bath contents from escaping and, if necessary, an optional additional air draw stage or wet draw after the material leaves the die assembly outlet Can be formed, eg, cast, at the outlet to function as a restraint that allows The microscopic shape of the inner surface of this lip at the outlet can be used to modify the surface texture of the surface coating of the extruded material.

  In one embodiment of the invention, the extrusion device is manufactured using a so-called LIGA process. The principle of the LIGA process is described in the book "Angewandte Mikrotechnik. LIGA-Laser-Feinwerktechnik" by Rainer Brueck and Andreas Schmidt (Herausgeber). Munich: Hanser Fachbuch, 2001.

  In the LIGA process, the conductive substrate is covered with a layer of resist. This resist is usually a poly (methyl methacrylate) (referred to as PMMP) based resist, but may be a poly (lacitde-coglycolide) resist, a polyimide resist or another suitable resist. A resist pattern is formed in the resist by lithographic techniques. The lithographic techniques used include photolithography, UV-lithography, or X-ray lithography. The smallest structure is created using synchrotron radiation. Alternatively, the resist pattern can be formed by laser or electron ablation.

  Typically, a layer of nickel, copper, gold, NiFe or NiP metal is subsequently placed on the resist pattern using electroformation. The conductive substrate is removed and the remaining resist pattern is melted to produce a mold insert. The mold insert is then filled with a plastic casting compound, and then the extrusion device is cast.

  By way of further example only, the support for the jacket and the tubular passage can also be made from two or more components, by laser ablation, or in other ways known to those skilled in the art. It should be understood that this method of making is modular and that many such modules can be assembled in parallel to produce multiple fibers or other forms of product simultaneously. The sheet material can be manufactured from rows or several rows of such modules. With such a module arrangement, a manifold is used to supply the dope to the inlet of the cylindrical passage, supply processing solvent, solution, gas or vapor to the jacket surrounding the cylindrical passage, and these from the jacket. It can be removed. Additional components can be added if desired. Potentially possible modifications to the illustrated arrangement will be apparent to those skilled in the art.

  Other methods of making a spinning device in which the walls of the tubular passage are composed of mostly or partially semi-permeable and / or porous materials will be known to those skilled in the art. By way of example only, these include micro-machining technology, laser ablation technology and lithography technology. In addition, it is understood that the wall of the cylindrical passage, which is roughly or partly composed of semipermeable / porous material, can also be incorporated into another type of spinning device, such as an electrospinning device. I want.

  The cylindrical passage or each cylindrical passage can be made self-starting and self-cleaning. It should be understood that it is time consuming and costly for the extruded material to block the spinning die during commercial production. In order to overcome this difficulty, the walls of the tubular passage can be constituted by two or more jackets arranged one after the other. The pressure of each of these jackets can be varied independently by methods that will be understood by those skilled in the art. The pressure change in the jacket can be used to change the diameter of the different areas of the cylindrical passage in a manner similar to a peristaltic pump and to pump out the dope at the outlet to initiate fiber withdrawal or remove the blockage. As a result, the pressure in the jacket decreases toward the outlet end of the cylindrical passage, thereby expanding the elastic wall of the cylindrical passage in the jacket. Here, when the pressure in the second jacket closer to the inlet end of the cylindrical passage increases, the area of the wall of the cylindrical passage running through this jacket tends to shrink to push the dope toward the outlet. Become. Alternatively, the pressure of the dope supplied to the cylindrical passage can be increased, and the diameter of the elastic cylindrical passage wall can be increased. It should be understood that both methods can be used together or sequentially. By using both methods, the passage wall is elastic so that the diameter of the tubular passage can be increased and the flow resistance can be reduced. It should be noted that increasing the dope pressure by using both methods also helps to eliminate activation and blockage of the tubular passage. By way of example only, it will be understood that rollers such as those used in peristaltic pumps can be used as another means of applying pressure to pump the dope to the outlet to initiate spinning or remove clogging. I want.

  The pressure in the sealed compartment surrounding the tubular passage can be controlled to define and modify the shape of the tubular passage to optimize spinning conditions. It should also be understood that semi-permeable or porous membranes can be used to introduce agents that aid in removal of clogged dies. Such agents include dilute solutions of alkali or alkaline buffer, ammonia vapor or solutions.

  When the cylindrical passage or each cylindrical passage has a tapered or divergent shape along the entire length or a part of its length, the filler particles or short fibers contained in the dope are the cylindrical passage. When flowing through, the orientation can be aligned using the well-known stretching flow principle. The substantially axial orientation of such filler particles or short fibers is created by a tapered tubular passage, while the divergent tubular passage has a hoop orientation substantially transverse to the major axis of the extruded material. It should be understood that it is created. Both orientation patterns give the fiber additional useful properties. The tapered or divergent shape of all or part of the tubular passages or each tubular passage is supplied to the tubular passage or other solvent or solution present in the dope produced by the phase separation process in the dope It should also be understood that it also serves to stretch and orient small fluid droplets of other phases or phases, or other non-polymerized polymers. The presence of stretched phase separation within the dope, the presence of stretched, well-oriented narrow inclusions formed by tapered or divergent cylindrical passages, add additional useful properties to the extruded material. give.

  This device optionally forms two or more fibers in parallel, twists around each other, crimps or wraps or coats on a former or It can be arranged to remain uncoated. The fiber can be pulled through the coating bath and subsequently through the tapering die to produce a “sea and island” composite, as understood by those skilled in the art. One or more rows of dies or one or more dies having slits or annular openings can be used for forming the sheet material.

  FIG. 1 shows a schematic apparatus for forming an extrusion material from an extrusion solution such as a liquid crystal polymer or other polymer or polymer mixture. This device comprises a dope reservoir 1 containing a dope 25, a pressure regulating valve or pump means 2 for maintaining a constant output pressure under normal operating conditions, a connecting pipe 3 and at least one further described in FIGS. A spinning die assembly 4 comprising a spinning tube or die is provided. A winding drum 5 of any known construction is drawn at a drawing speed and takes up the extruded material coming out from the outlet of the die assembly 3 with a constant winding tension on the reel. The pressure regulating valve or pump means 2 may be any device that constantly produces a constant pressure, usually known to those skilled in the art.

  The arrangement shown in FIG. 1 is purely exemplary and additional components to the arrangement shown in FIG. 1 will be apparent to those skilled in the art. In use, the dope 25 is transferred from the raw material reservoir 1 to the inlet of the spinning die assembly 4 via the supply connection pipe 3 at a constant low pressure by means of a regulating valve or pump means 2.

  The apparatus can further comprise one or more sensors schematically shown at 70. The one or more sensors 70 are connected to a microprocessor 75 that receives output from the one or more sensors 70. The sensor 70 is preferably integral with the die assembly 4, i.e. assembled at the same manufacturing stage at the same time. The output of the microprocessor 75 can be used to control parameters of the extrusion process such as extrusion speed, take-up tension pull rate and pH. It should further be appreciated that the components of the microprocessor 75 can be made integral with the device. In particular, this component can be assembled together with other parts of the device.

  The die assembly 4 is shown in more detail in FIGS. The die assembly 4 comprises a first spinning tube or die 8 upstream of the second spinning tube or die 12, both of which are cylindrical passages 17 for the spinning solution 25 passing through the die assembly 4. Is defined. The die 12 has an inner wall 18 and is divided into an initial zone 60 and a subsequent zone 62. Dies 8 and 12 are made of a semi-permeable and / or porous material such as a cellulose acetate membrane or sheet. Another example of a suitable semi-permeable and / or porous material is a diethylaminoethyl or carboxyl or carboxymethyl group which serves to keep the dope containing the protein in a state suitable for spinning. Hollow fiber membrane materials such as polysulfone, polyethylene oxide-polysulfone mixtures, hollow fiber membranes made from silicon or polyacrylonitrile can also be used. The exclusion limit chosen for the semipermeable membrane depends on the small molecular weight size of the components of the spinning dope 25, but is usually less than 12 kilodaltons (kDa).

  The die 8 is held at its upstream end by a tapered adapter 6 located at the inlet end of the die assembly 4 and at its downstream end is held by a tapered adapter 7 located internally in the die assembly 4. . The die 8 is held by an adapter 7 at its upstream end and held by a spigot 13 at the outlet of the die assembly 4 at its downstream end. The die 8 has a tapered, preferably hyperbolic, internal passage, and its geometric taper is preferably continuous with the internal passage of the die 12. This can be done by softening the semi-permeable tube or die in a suitably tapered heated mandrel during assembly before fitting the spinning tube or die into the device or in this field It can be achieved by other methods understood by skilled workers. The internal passages of the dies 8 and 12 together form a cylindrical passage 17 from the inlet to the outlet of the spinning solution die assembly 4.

  The jacket 9 surrounding the die 8 can include a fluid such as a solvent, solution, gas or vapor to control the processing conditions within the spinning tube or die 8. The jacket 9 is provided with an inlet 10 and an outlet 11 in order to control the flow of fluid inside and outside the jacket. A separate jacket 14 surrounds the tube or die 12 and a fluid inlet 15 and fluid, such as a solvent, solution or gas that contacts the semi-permeable / porous wall of the die 12 can pass into and out of the jacket 14. A fluid outlet 16 is attached.

  As an alternative to the illustrated die 8 having a semi-permeable wall, the die 8 can be constructed from a material that is not semi-permeable or porous, but is preferably tapered, eg, tapered, within the jacket 9 Can be controlled by a fluid circulating at a predetermined temperature.

  In operation, a spinning solution or dope 25, for example a polymer solution, is supplied to the inlet of the die 8 and is processed when the dope passes along the cylindrical passage 17, first when it passes through the die 8, 2 is processed when passing through the die 12. The fluid passing through the jacket 9 may simply help to heat or hold the dope 25 at the correct temperature or to apply the correct external pressure to the die 8 wall. In this case, it is not essential that the die walls are made of semi-permeable and / or material. The temperature of the dies 8 and 12 for extruding the protein-containing dope 25 must normally be kept at about 20 ° C., but spinning can be performed at a low temperature of 2 ° C. to a high temperature of 40 ° C. The temperature of the dies 8 and 12 for dope extrusion can more generally be as high as 100 ° C. if the material is not destroyed at that temperature. The pressure of the fluid, liquid or gas in the jacket surrounding the wall of the cylindrical passage 17 is usually kept close to the pressure at which the dope 25 is supplied to the die assembly 4. However, this pressure can be slightly higher or lower depending on the shape of the die and the strength of the generally flexible semi-permeable and / or porous membrane. The “chemical” treatment of the dope 25 occurs during “drawdown” as the dope 25 moves through the die 12, but if the walls of the die 8 are made of at least partially semi-permeable material. This may happen when the dope 25 moves through the die 8. 2 and 3, the sudden pull away from the wall of the die 12 at the 12A position of the dope 25 indicates an internal drawdown of the “fiber”. This occurs at the boundary between the first zone 60 and the subsequent zone 62. This is one feature of the present invention because in existing processes, drawdown always begins at the outer opening 13 (ie, the extrusion orifice) of the die and not before it. The pulling of the “fibers” from the die wall at the 12A position is such that the force required to create an extension flow in the cylindrical die 12 that creates a new surface causes the dope to contact the die wall and cause the die 12 to move. Wake up in a place exactly below the force required to flow through. This is a place where the surface energy of the inner wall 18 is lower than the surface energy of the dope 25. The position of 12A depends on the varying rheological properties of the dope, the speed and force of drawing, the surface properties of the die 12, the surface properties of the lining of the die 12, and the properties of the aqueous phase surrounding the dope and dope. The position of 12A should be at least 0.5 mm from the external opening or spigot 13.

  In one embodiment of the invention, the surface 66 of the inner wall 18 of the die 12 is provided with a ridge 68 to facilitate fiber drawdown at 12A. This is shown in FIGS. These ridges 68 have a height that is typically less than 10% of the diameter of the die 12. Normally, the diameter of the die 12 at this position is 20 μm, and the raised portion 68 is 0.5 μm high. This ridge 68 can be between 100 nm and 20 μm high. Fiber drawdown is believed to occur because the rod-like unit 64 in the dope 25 is positioned substantially perpendicular to the inner wall 18 in the first zone 60 of the die 8 and die 12. At the 12A position, these rod-like units begin “tumble” within the dope, resulting in an increase in viscosity and a reduction in the surface energy of the dope 25. This causes a change in the rheology of the dope, aided by the presence of the ridges 68 on the inner wall 18 and helps initiate fiber drawdown.

  As is commonly understood by those skilled in the art, the temperature, pH, osmotic pressure, colloid osmotic pressure, solvent component, ionic component, hydrostatic pressure or other physics supplied to the jacket. Mechanical or chemical factors control or regulate the condition inside the cylindrical passage 17 and consequently the extrusion process. The fluid chemistry supplied to the jacket 9 can pass through the semi-permeable and / or porous walls of the cylindrical passage 17 and “treat” the dope 25 passing therethrough. Chemicals in the dope 25 can also pass outwardly through the semi-permeable and / or porous walls of the cylindrical passage 17. The fluid supplied to the dope 17 will obviously vary depending on the type of dope 25 used and the semi-permeable and / or porous membrane used. However, by way of example only, for spinning of a concentrated major ampullate gland protein solution, jacket 9 is used to help maintain the protein folded state. Can usually contain 100 millimolar (mM) Tris or PIPES buffer solution at pH 7.4 and 400 millimolar sodium chloride. Jacket 14 can include a lower pH, typically below 5.0, 100 millimolar ammonium acetate buffer solution, and 250 millimolar potassium chloride to promote protein non-folding / refolding. High molecular weight polyethylene glycol can be added to the solution in both jackets to maintain or reduce the concentration of water in the dope 25.

  It will be appreciated that the spinning tube or die 12 can be hank, coiled or otherwise disposed between the tapered collar 7 and the spout 13. The diameter and cross-sectional shape of the outlet 13 can be changed and adjusted to match the diameter and cross-sectional shape of the material to be formed. For formed products having a circular cross-section, the typical diameter of the outlet is 1 to 100 μm, and the typical diameter of the inlet to the tubular passage 17 is 25 to less than the outlet diameter depending on the extent of the extension flow. It will be 150 times bigger. It should be understood that the arrangements and ratios shown in FIG. 2 are purely exemplary and therefore additional components can be added if desired. Potentially possible modifications to the arrangement shown in FIG. 2 will be apparent to those skilled in the art.

  FIG. 4 shows a module that includes three spinning tubes or dies 12 mounted in a housing that defines three “jackets” 14. The same numbering as in the previous embodiment is used to identify the same or similar parts. The arrangements and ratios shown in FIG. 2 are purely exemplary and therefore additional components can be added if desired. Potentially possible modifications to the arrangement shown in FIG. 4 will be apparent to those skilled in the art, including providing some or more dies 12 or jackets 14.

  FIG. 5 shows how two or more module units assembled from the apparatus shown in FIG. 4 can be held together so that multiple extruded fibers can be produced. It should be understood that the arrangements and ratios shown in FIG. 5 are purely exemplary and therefore additional components can be added if desired. Potentially possible modifications to the arrangement shown in FIG. 5 will be apparent to those skilled in the art.

  The transmittance or porosity of the wall of the tubular passage can be the same over the entire length of the tubular passage. However, as an alternative, if the tubular passage 17 passes through a plurality of treatment zones, the permeability / voidage of the wall of the tubular passage is different from the treatment zone to the treatment zone and the semi-permeability of the tubular passage Or it can be changed using a porous material. Therefore, the wall of the cylindrical passage 17 is provided over the entire length of the tubular passage 17 over the entire length of the tubular passage 17. Porous material of the same porosity, porous material of different porosity for different parts of the passage, or semi-permeable material and part of the tubular passage for one or more parts of the length of the tubular passage A porous material can be provided for one or more portions. As described above, certain portions of the wall of the tubular passage can be impermeable. By way of example only, suitable semipermeable materials include cellulose derivatives, expanded polytetrafluoroethylene (PTFE), polysulfone, polyethylene oxide-polysulfone mixtures, silicon-polyacrylonitrile mixtures. By way of example only, suitable porous materials include polyacrylates, poly (lacitde-coglycolide), porous PTFE, porous silicon, porous polyethylene, cellulose derivatives and chitosan.

  The device of the present invention is a copolymer of synthetic, artificial, natural, modified, all solutions of lyotropic liquid crystal polymers, or recombinant proteins or analogs derived therefrom or mixtures thereof. It should be understood that it is suitable for forming sheet fibers from a mixture or solution. By way of example only, these include collagen, certain cellulose derivatives, spidroin, fibroin, spidloin or fibroin-based recombinant protein analogs, and poly (p-phenylene terephthalate). This method is also suitable for use with other polymers or polymer mixtures, which may be aqueous or non-aqueous, dissolved in a solvent, and may be a protein solution, cellulose or chitin solution. One or more semi-permeable and / or porous processing zones are also used for dies or die assemblies having substantially annular or elongated slit openings used to form sheet material. Please understand that you can.

1 is an overall schematic view of an apparatus for forming an extruded material from a spinning solution. FIG. 2 is a schematic cross-sectional view along the longitudinal axis of the die assembly of the apparatus shown in FIG. 1. FIG. 3 is a schematic perspective view of the die assembly shown in FIG. 2. FIG. 6 is a schematic exploded view showing another embodiment of a die assembly of an apparatus according to the present invention. FIG. 5 shows the multiple die assemblies of FIG. 4 assembled together in one unit so that multiple fibers can be extruded. It is a figure which shows tumbling of a rod-shaped element within a cylindrical channel | path. It is sectional drawing of a cylindrical channel | path.

Claims (32)

  At least one first reservoir (1) connected at a first end to a first opening of a plurality of adjustment modules (4) with a passageway (17) through which material (25) can be extruded. An extrusion apparatus comprising: an extrusion apparatus (4) having at least 1,000 passages (17) per square meter of cross-sectional area.   The extrusion device according to claim 1, wherein the adjustment module (4) further comprises at least one second reservoir.   3. Extrusion device according to claim 2, wherein the second reservoir is fluidly connected to at least one opening of at least one of the passages (17).   The extrusion device according to any one of claims 1 to 3, further comprising a sensor (70).   The extrusion device according to any one of claims 1 to 4, further comprising at least one of the following sensors: a pressure sensor, a temperature sensor, a chemical sensor, a pH sensor and / or a light scattering sensor.   6. Extrusion device according to any one of the preceding claims, wherein at least one of the adjustment modules (4) comprises at least one single sensor (70).   7. Extrusion device according to any one of the preceding claims, wherein the sensor is integral with the adjustment module (4).   8. Extrusion device according to any one of the preceding claims, wherein the adjustment module (4) also further comprises one or more pumps (2).   The extrusion device according to any one of the preceding claims, wherein the adjustment module (4) further comprises a piezoelectric or vibration pump (2).   10. Extrusion device according to any one of the preceding claims, wherein the tubular passage (17) has a flow inlet.   11. Extrusion device according to any one of the preceding claims, wherein the inner wall of the passage (17) is made from a permeable material.   12. Extrusion device according to any one of the preceding claims, wherein the adjustment module (4) is injection molded.   13. Extrusion device according to any one of the preceding claims, wherein the adjustment module (4) is formed by ablation.   14. In operation, the material (25) is drawn down at a first distance at least 0.5 mm away from the outer outlet opening (13) in the passage (17). The extrusion apparatus as described in a term.   The component of material (25) in the first zone in one of said passages (17) forms a rod-like unit (64) substantially perpendicular to the inner surface of said passage (17). The extrusion apparatus as described in any one of -14.   The component of the material (25) in one subsequent zone (62) of the passage (17) has a rod-like unit (64) that tumbles when the material (25) flows in the passage (17); The extrusion apparatus as described in any one of Claims 1-15.   17. Extrusion device according to any one of the preceding claims, further comprising a raised surface (66) having a plurality of raised portions (60) on the inner surface of the passage (17).   18. Extrusion device according to claim 17, wherein the height of the ridge (60) is less than 10% of the diameter of the passage (17).   19. Extrusion device according to claim 17 or 18, wherein the raised surface (66) has a lower surface energy than the surface energy of the material (25).   20. Extrusion device according to any one of claims 17 to 19, wherein the raised portion (60) is oriented substantially along the long axis of the tubular passage (17).   21. Extrusion device according to any one of claims 17 to 20, wherein the ridge (60) is made of a hydrophobic material.   21. Extrusion device according to any one of claims 17 to 20, wherein the ridge (60) is coated with a hydrophobic material.   23. Extrusion device according to any one of claims 17 to 22, wherein the drawdown occurs substantially adjacent to the raised shaped surface covering (66).   The extrusion device according to any one of claims 1 to 23, wherein the material (25) is a liquid crystal polymer.   The extrusion device according to any one of claims 1 to 24, further comprising a cleaning device.   26. Extrusion device according to claim 25, wherein the cleaning device consists of a permeable inner wall of the passage (17) through which a cleaning agent is introduced.   27. The extrusion device of claim 26, wherein the cleaning agent is an alkaline fluid.   28. Extrusion device according to any one of claims 3 to 27, further comprising a microprocessor (75) connected to the sensor (70).   29. Extrusion device according to claim 28, wherein the microprocessor (75) has an output for sending a signal to control at least one parameter of the extrusion device.   30. Extrusion device according to claim 28 or 29, wherein the microprocessor (75) is integral with the adjustment module (4).   The extrusion device according to any one of claims 1 to 30, wherein the extrusion device is a spinning device. The object formed from the extrusion apparatus as described in any one of Claims 1-31.

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